Just a quick note on sound.
Now that I've run trains with and without sound, I definitely want sound. It does enhance the operation. In addition, the QSI Quantum Revolution is finally being released, so I can't wait. I only need a couple more locomotives for the basics, so instead of buying more I'll start adding sound.
5/23/2008 - Hmmmm. Didn't quite work out that way. I've got a bunch more locomotives and only one has sound (or a decoder) so far. And that one came preinstalled.